Osteoarthritis, the major degenerative disease of weight-bearing joint surfaces, affects approximately 25 percent of people over 50. Thus, in the US, approximately 37 million people suffer from arthritis with annual healthcare costs of approximately 8.6 billion dollars. Additionally, annual costs for cartilage repair from acute joint injury (meniscal lesions, patellar surface damage and chondromalacia) exceeds 1 billion dollars. Because cartilage cannot self repair after injury or disease, this problem will continue to increase without new therapeutic approaches. A single injection or application of the thrombin peptide TP508 nearly doubles the rate of fresh fracture healing or healing of full dermal wounds. This acceleration involves cell recruitment, increased matrix accumulation, and stimulation of cell proliferation. To determine the feasibility of Phase II development of TP508 products for cartilage repair or restoration of arthritic joint damage, we will: i) determine if TP508 stimulates matrix synthesis and cell proliferation in primary chondrocytes and determine if TP508 can decrease collagenase production; ii) select appropriate doses; and iii) establish assays useful in product formulation. The development of cost- effective, TP508 injectable product for cartilage repair could revolutionize clinical treatment of arthritis and joint repair, reduce healthcare costs, and improve quality of life for millions of people. PROPOSED COMMERCIAL APPLICATION Proposed product will be an injectable dosage form of the TP508 peptide for treatment of joint surfaces that have undergone cartilage injury or degeneration. The peptide will be formulated for delivery in saline, collagen or hyaluronic acid. In the US, the combined annual market for therapies treating either osteoarthritis or joint injury caused by acute trauma is estimated to be 9.6 billion dollars. Inducing cartilage repair without surgery offers potential hope for millions of people and will greatly reduce health care costs worldwide.